Moldboard snow plows are typically mounted to the front end of a truck or vehicle by means of a bracket or hitch mechanism which permits easy removal of the plow for repair or replacement or storage. The hitch mechanism for a moldboard plow often includes hydraulics which effect adjustment of the angle of the plow by pivotal movement about a vertical pivot axis so that the plow may be centered or tilted to the left or right of the direction of vehicle travel. Typically, in plowing operations, especially in the United States where driving occurs on the right-hand side of road, the plow will be canted or tilted so that the right-hand side of a straight moldboard plow trails the left-hand side. In this manner, snow is pushed or ejected to the right as the vehicle moves forward advancing the plow through snow. Of course, in certain circumstances the angle or inclination of the plow about its vertical axis must be adjusted. Additionally, the plow may need to be raised or lowered. For example, when plowing on an upward incline it may be necessary to raise the plow and tilt the plow so that the plow will move appropriately up the incline. Similarly, when plowing downhill, it may be desirable to lower the plow and perhaps tilt the plow downwardly.
There are various straight moldboard snow plows and associated mounting brackets available in the marketplace. For example, the Gledhill Road Machinery Company of Galion, Ohio manufactures various moldboard plow models. Valk Manufacturing Company of Carlisle, Pa. also makes similar snow plow constructions. Lawtons' Equipment, Inc., of Paris, Ill. also makes similar snow plow constructions.
The support bracket available from these companies for holding a plow on the front of a vehicle also has a variety of constructions. Typically the support bracket includes a forwardly extending support mounted on a frame. The support may be pivotally attached to the frame. The frame may include an actuator and guide member which imparts angular movement to the support bracket on the frame about a vertical pivot. The construction is typically made from steel angle iron.
While the known prior art moldboard snow plows and associated mounting brackets work well, a need persists for a snow plow brackets support construction which is more compact and is a lighter weight mechanism for attaching a moldboard plow to a vehicle. Additionally, a need for improved maneuverability persists with respect to such plows and associated mounting brackets. Also, when using hydraulic cylinders to effect a change in the angle of such a plow mounted on a bracket, two cylinders have been required typically to effect operation. A need, therefore, to provide a mounting bracket mechanism for moldboard snow plows which utilizes a single cylinder for plow angle control persists inasmuch as a single cylinder will be less costly and will operate more quickly and effectively because less hydraulic pumping will be required in order to effect operation of a single cylinder.
The effect of the weight of the plow and support bracket on the front end of a plow vehicle tends to cause the vehicle to tip forward. For this reason, it is often necessary to load or weight the rear end of a vehicle. By providing a plow construction which has a lighter weight and a bracket attachment mechanism which has a lighter weight and which permits positioning of the plow closer to the vehicle, the center of gravity of the snow plow and the bracket associated therewith may be maintained closer to the center of gravity of the vehicle. This is a desirable objective.
Thus, there are many reasons to provide an improved plow construction and more particularly a mold board plow construction and bracket for attachment thereof to a vehicle.